Method of forming laminated foam counter and table tops

Abstract

An inventive method for producing a laminated molded countertop includes the steps of placing the surface laminate material into a mold, applying a layer of polyurethane foam to an interior side of the laminate material, applying a reinforcing member, if necessary, on top of the layer of polyurethane foam, applying a second layer of polyurethane foam over the reinforcing member and closing the mold. A resultant molded article has an exterior surface laminated thereto due only to the forces generated by the polyurethane foam during the time when it is expanding and solidifying.

I claim as my invention: 
     
       1. A method of forming laminated articles of a selected shape with a selected laminated surface material using a preformed, openable, mold having at least two parts comprising the steps of: taping the pieces of the selected surface material together by applying tape on exterior surfaces thereof across adjacent edges of different pieces of surface material to prevent leakage of the expandable foam material therebetween while the expandable material is expanding and applying pressure to the surface material;   placing the exteriorly taped surface material in the mold cavity of the first mold part;   applying a first layer of mixed expandable foam material to at least a part of an interior surface of one piece of selected surface material within the first mold part;   positioning the reinforcing member upon the first layer of mixed expandable foam;   applying a second layer of mixed expandable foam over at least a portion of the reinforcing member;   applying a layer of backing surface material over the second layer of expandable material in the first mold part before the mold is closed;   closing the mold;   clamping the mold closed for a selected time such that the expandable foam material fully expands throughout the mold, solidifies, cures and bonds to the interior surfaces of the selected surface material due to the pressure exerted by the expandable foam material on the interior surfaces of the selected surface material; and   opening the mold and removing the completed, laminated article.   
     
     
       2. The method according to claim 1, including an additional step of mixing component parts of the expandable foam material to form a quantity of mixed expandable foam. 
     
     
       3. The method according to claim 2, wherein the step of mixing comprises placing the component parts of the expandable foam material into a mixing container and mixing the component parts with a mechanical agitator. 
     
     
       4. The method according to claim 3, wherein the step of applying a first layer comprises mechanically spreading a quantity of expandable foam material on the part of the interior surface of the selected surface material. 
     
     
       5. The method according to claim 4, wherein the step of applying a first layer comprises: supplying the components of the expandable foam material to an enclosed mixing chamber;   mixing the components in the enclosed mixing chamber under pressure;   spraying the mixed expandable foam material under pressure against the part of the interior surface of the selected surface material.   
     
     
       6. The method according to claim 1, including the further steps of: selectively drilling or cutting the completed, laminated article;   coating the drilled or cut surfaces of the expanded foam material with a selected urethane elastomer.   
     
     
       7. A method of forming molded countertops of a selected size and shape with a thin surface material laminated thereto using a mold having at least two parts comprising the steps of: taping a plurality of pieces of the surface material together with the exterior sides oriented outwardly and with the tape placed on the exterior sides;   placing the exteriorly taped pieces of surface material into the mold;   applying a layer of mixed expandable foam material to at least a part of one interior side of the surface material in the mold;   closing the mold for a selected time such that the expandable foam material fully expands throughout the mold, solidifies and bonds to the interior sides of the surface material due to the pressure exerted by the expanding foam material on the interior sides of the surface material;   opening the mold and removing the completed laminated countertop;   selectively drilling or cutting the completed, laminated countertop;   and coating the drilled or cut surfaces of the expanded foam material with a selected urethane elastomer.   
     
     
       8. The method according to claim 7 wherein the step of applying comprises: supplying the components of the expandable foam material to an enclosed mixing chamber;   mixing the components in the enclosed mixing chamber under pressure;   spraying the mixed expandable foam material under pressure against the part of the interior surface of the selected surface material.   
     
     
       9. The method according to claim 7, including a further step of: applying a layer of backing surface material between the layer of expandable material in the first mold part, and the second mold part before the mold is closed.   
     
     
       10. The method according to claim 9, wherein the step of applying a layer of mixed expandable foam material comprises: applying a first layer of mixed expandable foam material to at least a part of an interior surface of one piece of selected surface material within the first mold part;   positioning a reinforcing member upon the first layer of mixed expandable foam;   applying a second layer of mixed expandable foam over at least a portion of the reinforcing member.